JPH0540700Y2 - - Google Patents

Description

[Detailed description of the invention] a. Field of industrial application The present invention relates to an absolute resolver device, and in particular, a device that obtains a multi-rotation absolute signal by incorporating a linear position detector consisting of a movable core and a fixed coil. Regarding improvements to make it so.

b. Prior Art A variety of configurations have been proposed for this type of absolute resolver device that has been used in the past.To describe a typical configuration, here we will list the names of documents showing the configuration. etc., but a conventional general configuration shown in FIG. 4 can be disclosed.

That is, what is indicated by the reference numeral 1 in FIG. 4 is the first resolver, and this first resolver 1
A first gear 3 is fixedly provided on the rotating shaft 2,
This first gear 3 has a rotating shaft 5 of a second resolver 4.
A second gear 6 fixedly provided meshes with the second gear 6.

Furthermore, the first gear 3 has a smaller diameter than the second gear 6, and has a reduction ratio of 1/n.

The conventional absolute resolver device is configured as described above, and its operation will be explained below.

First, when the rotating shaft 2 of the first resolver 1 is connected to a rotating member such as a machine tool or a robot to be detected, the rotating shaft 2 rotates, and the rotation angle is detected by the first resolver 1. Furthermore, when this first resolver 1 rotates one rotation or more, the multi-rotation state of the rotating shaft 2 is reduced to 1/n, and the second resolver 4
The multi-rotation state of the first resolver 1 is detected by the second resolver 4, and a multi-rotation absolute signal is obtained. In another conventional example, one resolver was used and the rotational speed was detected by a reed switch.

c. Problems to be solved by the invention Since the conventional multi-rotation type absolute resolver device was constructed as described above, it had the following problems.

That is, since a plurality of resolvers are required, the diameter and length of the entire resolver device become large, resulting in a significant increase in cost.

Further, in the case of other conventional examples, since a reed switch is used, it is necessary to back up the power supply for the counter circuit when the power is turned off, and there is also a problem in the reliability of the reed switch.

The present invention was made to solve the above problems, and in particular, by providing a linear position detector consisting of a movable core and a fixed coil in one resolver, a multi-rotation absolute sensor is provided. An object of the present invention is to provide an absolute resolver device that can obtain signals.

d Means for solving the problem The absolute resolver device according to the present invention is
a stator portion provided on the inner surface of the casing, a rotating shaft rotatably provided on a bearing of the casing and having a rotor portion, a feed screw portion formed on the rotating shaft, and a feed screw portion engaged with the feed screw portion. The stator includes a movable core that is provided to be movable in the axial direction by rotation of a threaded portion, and a fixed coil that is provided in the casing and is formed in a cylindrical shape at an outer peripheral position corresponding to the movable core. The rotor section and the rotor section constitute a resolver section, and the movable core and the fixed coil constitute a linear position detector for detecting the number of rotations.

e Effect In the absolute resolver device according to the present invention, one resolver is provided with a linear position detector that moves in conjunction with the rotating shaft of the resolver, so the multi-rotation state of the resolver is Since it is detected by a linear position detector, an absolute signal in a multi-rotation state can be obtained with one resolver, and a stable absolute signal can be obtained even after the power is turned off.

f. Embodiments Hereinafter, preferred embodiments of the absolute resolver device according to the present invention will be described in detail with reference to the drawings.

Note that the same reference numerals will be used to describe parts that are the same or equivalent to those of the prior art.

What is shown in FIGS. 1 to 3 is to show an absolute resolver device according to the present invention, and what is designated by the reference numeral 1 in the figures is a resolver. A stator core 8a and a stator coil 8b that constitute the stator section 8 are provided on the inner surface 7a of the casing 7.

A rotating shaft 2 is rotatably provided in a pair of bearings 9 and 9a provided at both ends of the casing 7, and the rotating shaft 2 has a substantially E-shaped cross-section. A rotor core 10a and a rotor coil 10b, which constitute the rotor section 10, are provided at the outer peripheral position.

A feed screw portion 1 made of a ball screw is formed in the center of the rotating shaft 2, and a non-threaded portion 11a at the end of the feed screw portion 11 is rotatably held by a bearing 9a.

The feed screw portion 11 has this feed screw portion 11.
A movable core 12 made of an electromagnetic material such as ferrite is provided which screws and engages with the rotary shaft 2. Since the feed screw portion 11 rotates in conjunction with the rotation of the rotating shaft 2, the movable core 12 is rotated as shown by the arrow. It can be moved in the axis direction shown.

A fixed coil 13 having a cylindrical shape and consisting of an excitation coil and an output coil (not shown) is disposed on the inner surface of the casing 7, and one end of the fixed coil 13 is connected to the inner surface 7a of the casing 7.
It is held by a coil bobbin 14 fixed to. The stator section 8 and rotor section 10 constitute a resolver section 15, and the movable core 12 and fixed coil 13 constitute a linear position detector 16.

The output signal 15a of the resolver section 15 is R/
After being converted into a digital signal by the D converter 17, it is input to the mixing circuit 18, and the output signal 16a of the linear position detector 16 is converted into a digital signal by the A/
After being converted into a digital signal by the D converter 19, it is input to the mixing circuit 18, which outputs an absolute rotational position signal 18a.

The absolute resolver device according to the present invention is
It is configured as described above, and its operation will be explained below.

First, the rotating shaft 2 is connected to a rotating member (not shown) such as a machine tool or a robot, and when the rotating shaft 2 rotates, the rotation of the rotor section 10 causes a resolver to be released from the stator section 8, similar to the action of a known resolver. Part 15
An output signal 15a consisting of a rotation angle signal as shown in FIG.
When the movable core 12 moves in the axial direction according to this rotational speed, the linear position detector 16 outputs an output voltage proportional to the amount of movement of the movable core 12 as an output signal 16a, as shown in FIG. do.

In the case described above, the outer periphery of the movable core 12 is configured to be non-circular, and when the feed screw portion 11 rotates, its outer periphery joins the fixed coil 13 and slides, so the movable core 12 does not rotate. Achieves only axial movement without

Therefore, since the output signal of the linear position detector 16 changes depending on the number of rotations of the resolver section 15, the output signal 16a from the linear position detector 16 and the output signal 15a from the resolver section 15 correspond to each number of rotations.
By mixing them in the mixing circuit 18, an absolute rotational position signal 18a can be obtained, and thereby the rotational speed and rotational angle of the rotating shaft 2 can be detected.

g. Effects of the invention The absolute resolver device according to the invention is
With the above configuration, the following effects can be obtained.

The rotor of the resolver part and the movable core of the linear position detector are installed on the rotating shaft, and the resolver part and the linear position detector are built into one resolver, resulting in an extremely compact configuration. Despite this, the rotation angle signal and the rotation speed signal can be output simultaneously.

Therefore, since this can be achieved with one resolver instead of using two resolvers as in the conventional configuration, the shape can be significantly reduced and it can be installed in narrow spaces where it was previously impossible to install. can also be installed.

[Brief explanation of the drawing]

Figures 1 to 3 are for showing the absolute resolver device according to the present invention. Figure 1 is a sectional view showing the overall configuration, and Figure 2 is a characteristic showing the output signal of the linear position detector. 3 are block diagrams, and FIG. 4 is a front view showing a conventional absolute resolver device. 2 is a rotating shaft, 7 is a casing, 8 is a stator section, 9, 9a are bearings, 10 is a rotor section, 11 is a feed screw section, 12 is a movable core, 13 is a fixed coil,
15 is a resolver section, and 16 is a linear position detector.

Claims (1)

[Claims for Utility Model Registration] (1) A rotating shaft 2 having a stator portion 8 provided on the inner surface of a casing 7 and a rotor portion 10 rotatably provided in bearings 9, 9a of the casing 7.
and a feed screw portion 11 formed on the rotating shaft 2.
a movable core 12 that is engaged with the feed screw portion 11 and is movable in the axial direction by rotation of the feed screw portion 11; and a movable core 12 that is provided on the casing 7 and corresponds to the movable core 12 It is provided with a fixed coil 13 formed in a cylindrical shape at an outer circumferential position, the stator section 8 and the rotor section 10 constitute a resolver section 15, and the output voltage changes due to a change in the coupling between the movable core 12 and the fixed coil 13. , an absolute resolver device characterized in that it constitutes a linear position detector 16 that can detect the number of revolutions. (2) The linear position detector 16 is connected to the rotor section 1.
1. The absolute resolver device according to claim 1, wherein the absolute resolver device is disposed at an inner position of 0.